8-bit Bus

The HP palmtop uses an 8-bit bus to interface with the PCMCIA slot. This bus is shared with the internal system ROM. The system RAM chips are on a separate 16-bit bus.

The PCMCIA standard allows the host to have an 8-bit bus and provides mechanisms by which 16-bit data transfers can be done with a pair of 8-bit accesses. Note that all PCMCIA standard cards have a 16-bit bus.

To save cost, some cards (such as the HP Speller/Thesaurus ROM card) use an 8-bit bus. These cards work fine in the HP palmtop, but may not work in other systems where the PCMCIA bus is 16 bits.